Writing instrument



FIG. 1 is a perspective view of a writing instrument;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a right elevation view thereof, the left elevation view is a mirror image thereof;

FIG. 4 is a rear elevation view thereof;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom plan view thereof. 

CLAIM The ornamental design for the writing instrument, as shown and described. 